The object of this research is to characterize a second-stage mutant of Escherichia coli which can grow on D-arabitol as the sole source of carbon and energy, both genetically and biochemically, and to explore its potential ability of growth on other 5-carbon polyhydric alcohols. By conjugation studies, we have succeeded in locating one of the genes responsible for growth on D-arabitol at 69 minutes of the E. coli genetic map. The gene product was identified as an NAD-linked dehydrogenase whose native substrate was most likely D-galactose. We have also found that D-arabitol was probably transported by the same system for D,L-1,2-propanediol. It was also possible to isolate third-stage mutants for growth on L-arabitol.